Many electronic devices employ mechanical switches, such as collapsing dome switches, as input mechanisms. Mechanical switches are generally reliable and provide inherent haptic feedback, as a user can often feel the mechanism of the switch closing.
However, as electronic devices have become more space-constrained, mechanical switches have presented problems. Many mechanical switches need a minimum amount of space to operate. For example, a typical dome switch needs about 200 microns of travel for the dome to collapse and close the switch. This is especially problematic in very thin electronic devices.
Solid-state input structures may greatly reduce required space and particularly travel. Many solid-state buttons travel 10 microns or less when force is exerted thereon. Solid-state buttons can use force sensors to determine when the button is pressed, for example. The force sensor registers a change in capacitance, resistance, current, voltage, or other electrical value when the solid-state button moves or flexes, even though such motion may be very small.
Solid-state input structures tend to require much more power than classic mechanical input structures and also have relatively high latency. Further, solid-state input structures are relatively complex and expensive when compared to mechanical input structures. However, a mechanical switch configured to amplify and transfer input travel to another location may combine several advantages of traditional mechanical switches and solid-state input structures. For example, such a low-travel mechanical switch would provide the lower-cost and increased simplicity of a traditional mechanical switch with the low vertical switch profile typical in solid-state input structures.